In applications where sensors are located at points of measurement to provide a faithful representation of the measured variables, it is necessary that the output be free of errors resulting from the inability of the sensors to respond to the rapidly changing input variables. Such measurement systems can be approximated by mathematical model of first-order time lag. For example, a system which employs a thermocouple for the measurement of temperature, the output represents a first-order delayed response to the temperature to be measured. It is desirable that this delay time be as small as possible. To a certain degree, this requirement can be met by reducing the thermal capacity of the dissimilar metals employed. However, further reduction of thermal capacity necessitates the use of filament-like thin metal strips which can result in a short lifetime of the thermocouple. When the environment of which the temperature is measured is a mass of fluid which passes the point of measurement at a constant flow rate, it is relatively easy to compensate for the delay time since the time constant of the first-order time lag remains constant. However, a variation of the flow rate can cause the time constant value to vary considerably, and as a result a measurement of the flow rate is additionally required to provide accurate compensation of the delay time.